Consolidated Condensed Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Apr. 30, 2019	10,000,000		(336,439)
Balance at Apr. 30, 2019	$ 1,000	$ 991	$ (4,743)	$ 48,598	$ 1,678	$ 47,524
Net income				7,901		7,901
Change in unrealized gains on securities, net of taxes					362	362
Purchase of treasury stock (in shares)			(16,493)
Purchase of treasury stock			$ (393)			(393)
Dividends declared				(3,863)		(3,863)
Balance (in shares) at Oct. 31, 2019	10,000,000		(352,932)
Balance at Oct. 31, 2019	$ 1,000	991	$ (5,136)	52,636	2,040	51,531
Balance (in shares) at Apr. 30, 2020	10,000,000		(383,279)
Balance at Apr. 30, 2020	$ 1,000	991	$ (5,957)	56,450	1,055	53,539
Net income				10,173		10,173
Change in unrealized gains on securities, net of taxes					(26)	(26)
Purchase of treasury stock (in shares)			(15,670)
Purchase of treasury stock			$ (422)			(422)
Dividends declared				(4,036)		(4,036)
Balance (in shares) at Oct. 31, 2020	10,000,000		(398,949)
Balance at Oct. 31, 2020	$ 1,000	$ 991	$ (6,379)	$ 62,587	$ 1,029	$ 59,228